JP2000119880A - Corrosion preventing structure of connecting part and method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the corrosion in the connecting part of a fixture and parts by coating a setscrew fastening the fixture and the parts with powder in which chemical reaction does not occur or hardly occur in a corrosive environment and lacked in affinity for metal. SOLUTION: At the time of executing tensle creep testing to a test piece 1 in a galvanizing soln. as a corrosive environment, screw parts on both ends of the test piece 1 are screwed into a chuck 2 as a fixture and are fitted thereto, and the exposed parts of both ends of the test piece 1 and the chuck 2 are coated with powder composed of ceramic or contg. ceramic to form a coating layer 3. As the powder, the ceramic one of alumina, zirconia, zircon or the like or the inorganic one suitable in a prescribed corrosive environment is used, is applied by spraying by jetting from a nozzle or coating by a brush or the like and is made easy to be peeled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for easily exchanging a part which is placed in a corrosive environment such as air, steam, water or an alkali or acidic liquid and is detachably attached to a fitting such as a joint. The present invention relates to a corrosion prevention structure and method that can be performed at a connection portion between a fixture and a component.

[0002]

2. Description of the Related Art In a corrosive environment such as air, water vapor, water, or an alkali or acidic liquid, parts that are screwed or inserted into fittings such as joints, or parts that are fastened with set screws after insertion are likely to corrode. If you try to remove it from the fixture, you will not be able to remove it because of the corrosion of the screw and insertion part or the corrosion of the set screw, and you will not be able to reuse it even if the fixture has corrosion resistance and is not corroded Often.

Conventionally, as a countermeasure against corrosion, it is often used to make a component or a fixture a material having corrosion resistance, for example, stainless steel, or to apply a rust preventive paint to the component or the fixture.

[0004]

Although stainless steel parts and fixtures exhibit excellent corrosion resistance in many corrosive environments, they are generally difficult and expensive to process. On the other hand, the application of rust preventive paint is relatively inexpensive, but depending on the corrosive environment, many of them cannot be used in, for example, high-temperature steam or alkali or acidic liquids. If the screw or the connecting portion of the insertion portion or the set screw is corroded, it is not easy to remove the component when replacing it. Even when the coating film is firmly fixed, it is not easy to remove the component.

[0005] The present invention is directed to a mounting device which can be easily removed from a mounting device when parts need to be replaced when used in a corrosive environment, for example, in the atmosphere, steam, water, or an alkali or acidic solution. It is an object of the present invention to provide a structure and a method for preventing corrosion at a connection portion between a tool and a component.

[0006]

The invention according to claim 1 relates to a corrosion prevention structure which achieves the above-mentioned object, and which is detachable by being screwed, inserted, or chucked into the attachment. In a corrosive environment, the chemical reaction does not occur or hardly occurs in the corrosive environment, and the metal and the connecting part to the part to be attached and / or the set screw for fixing the fitting and the part at the connecting part. Characterized in that it is coated with a powder lacking affinity.

According to the present invention, corrosion of the connection portion and the set screw is prevented by coating the connection portion or the set screw between the component and the attachment with a powder which does not or does not easily cause a chemical reaction with the corrosive environment. . In addition, since the powder has no or little affinity with a connecting portion made of metal or a set screw, it can be easily peeled off by hitting with a hammer or the like. The mounting tool of the present invention is not particularly limited as long as the component is screwed, inserted, or chucked. Examples of such a member include a joint and a chuck.

The powder used in the present invention is, for example, alumina,
A ceramic or other inorganic material such as zirconia or zircon that does not or hardly cause a chemical reaction in a corrosive environment and lacks affinity for metals. If it can be applied with
It need not be applicable to all corrosive environments. The invention according to claim 2 relates to a method for preventing corrosion, and relates to a connection part and / or connection between a fitting and a component which is screwed, inserted, or chucked to the fitting and detachably attached. Water or a solvent is used as a solvent in a set screw for fixing a fitting and a part in a part, and a chemical reaction with a corrosive environment that does not or hardly occur in a corrosive environment and powder that lacks affinity for metals It is characterized in that it is coated with a solution having a body as a solute.

The powder of the present invention is the same as the powder of the first aspect of the present invention, and the coating is performed by, for example, spraying by spraying from a nozzle or painting with a brush or brush. It is desirable that the fixture in each of the above-described inventions has corrosion resistance. However, if the entire fitting is covered with powder, there is no problem even if it does not have corrosion resistance.

A third aspect of the present invention is characterized in that, in the second aspect of the present invention, the whole fixture is covered with powder. The invention according to claim 4 is another invention relating to a corrosion prevention structure. In the corrosion prevention structure at a connection portion between a component and a component to be mounted by screwing or inserting into a corrosion-resistant mounting device, It is characterized in that a member that does not or does not easily cause a chemical reaction with the corrosive environment in the corrosive environment and is interposed between the divided pieces and that lacks affinity for metals is interposed.

In the present invention, the part in contact with the corrosive environment and the split piece at the end of the fixture are integrated by corrosion of the part.
Parts that are screwed or inserted into the split piece at the end of the fixture and the other split piece that interposes the member do not come into contact with the corrosive environment, so there is no integration by corrosion with other split pieces, and therefore other split pieces are It can be easily separated from the part and the divided piece at the end of the fixture integrated with the part.

The mounting tool of the present invention is not particularly limited as long as the component is screwed or inserted. A joint is a typical example. The invention according to claim 5 is another invention relating to a method for preventing corrosion, in which a corrosion-resistant fixture is divided so that a chemical reaction with the corrosive environment does not occur in the corrosive environment between the divided pieces, or hardly occurs. In addition, a component having no corrosion resistance is screwed or inserted into the fitting with a member lacking affinity for metal interposed therebetween.

In each of the above inventions, the same member as the powder used in the first to third aspects of the present invention is used as the member to be sandwiched between the divided mounting members.

[0014]

1 and 2 show a test piece used for performing a tensile creep test specified in JIS Z 2271 in a zinc plating solution as a corrosive environment, and is shown in FIG. A screw (not shown) at both ends of the test piece 1 is screwed into a chuck 2 as a fixture, and exposed portions at both ends of the test piece 1 and the chuck 2 are made of ceramic or powder containing ceramic. The applied coating layer 3 is formed.

As the ceramic used in the present invention, a ceramic-containing coating agent such as Ceracoat 22 (trade name) manufactured by Odeck Co., Ltd., BN coat (trade name) manufactured by the company, MZS15 (trade name) manufactured by the company, White Seven (trade name) etc. are used, the former three are powdered and mixed with water as a solvent and applied with a brush, and the latter White Seven (trade name) is kneaded and squeezed out Then it is applied.

The test piece 5 shown in FIG. 2 has a chuck 6 as a fixture in which ceramics 7 as members are interposed between divided pieces 6a, 6b and 6c, with both ends divided into single dimensions.
Screwed into both ends. The same ceramic as in the above embodiment is used for the ceramic of this embodiment.

[0017]

EXAMPLE 1 As shown in FIG. 1, screw portions at both ends of a 12 mm square NAGP material test piece 1 were screwed into a stainless steel (SUS316) chuck 2 and then CERACOAT 22 (trade name) manufactured by ODEC Co., Ltd. ) And water at a weight ratio of 1: 1 were applied to the entire surface of the chuck 2 and the end surface of the test piece 1 with a brush. After drying, it was immersed in a galvanizing solution and subjected to a creep test. After the test, when the test piece 1 was immersed in the plating solution for 100 hours and pulled up, the test piece 1 where the Seracoat 22 (trade name) was not applied was corroded and ragged and became thin. There was no corrosion in the part, and the coating layer was easily peeled off when hit with a hammer. Thereafter, when the chuck 2 was rotated in the direction in which the screw was loosened, the chuck 2 was rotated in the direction in which the screw was loosened, and the chuck 2 could be removed from the test piece 1.

Embodiment 2 As shown in FIG. 2, both ends are divided into divided pieces 6a, 6b, 6
In the same manner as in Example 1, Ceracoat 22 (trade name) manufactured by ODEC Co., Ltd. was applied to each contact surface, dried and combined, and then the test piece 1 of Example 1 was attached to the stainless steel (SUS316) chuck 6. The same test piece 5 as above was screwed in and attached. Then, it was immersed in a plating solution under the same conditions as in Example 1 and subjected to a creep test to pull it up. as a result,
The test piece 5 showed the same corrosion pattern as the test piece 1 of the first embodiment, but the corrosion was hardly caused on the chuck 6 and the test piece 5 could be reused. However, the split pieces 6b and 6c could be removed from the test piece 5.

[0019]

According to the first and second aspects of the present invention, the corrosion of the connecting portion and the set screw is prevented, and the coating layer of the powder is easily peeled off by hitting with a hammer or the like. It can be easily removed and reused. According to the third aspect of the present invention, if the entire mounting bracket is covered with the powder, it is not necessary to use a corrosion-resistant material for the mounting bracket.

According to the fourth and fifth aspects of the present invention, the mounting part where the part is screwed or inserted and does not come into contact with the corrosive environment can be detached and separated from the end of the mounting part integrated with the corroded part. And most of the fixtures can be reused.

[Brief description of the drawings]

FIG. 1 is a partial sectional front view showing an embodiment of the present invention.

FIG. 2 is a front view showing another embodiment of the present invention.

[Explanation of symbols] 1, 5, test piece 2, 6, chuck 3, coating layer 7, ceramic

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takuji Hamada 1-24 Tsukiji-cho, Kure-shi, Hiroshima Pref. (72) Inventor Ko Ko 1-24 Tsukiji-cho, Kure-shi Hiroshima Pref. Term (reference) 4K062 AA01 AA05 BA17 BC30 FA18 FA20 GA01

Claims (5)

[Claims] 1. A connection part between a fitting and a part which is screwed, inserted, or chucked to the fitting and which is detachably attached, and / or the fitting and the part are fastened at the connection part. A corrosion preventing structure for a connecting portion, wherein a set screw that is formed is coated with a powder that does not or hardly cause a chemical reaction with the corrosive environment in a corrosive environment and that lacks affinity for metals. 2. A connection portion between a fitting and a component which is screwed, inserted, or chucked to the fitting and which is removably attached, and / or the fitting and the component are fastened at the connection portion. Coating a set screw with water or a solvent as a solvent, in a corrosive environment, a solution in which a chemical reaction with the corrosive environment does not occur or is unlikely to occur, and the solute is a powder that lacks affinity for metals. A method for preventing corrosion of a connection portion, characterized in that: 3. The method as claimed in claim 2, wherein the entire mounting is coated with a powder. 4. A corrosion prevention structure at a connecting portion between a component and a fitting which is mounted by screwing or inserting into a fitting having corrosion resistance, wherein the fitting is divided into a plurality of pieces in a corrosive environment. A corrosion preventing structure for a connecting portion, characterized in that a chemical reaction does not occur or hardly occurs in a corrosive environment, and a member lacking affinity for metal is interposed. 5. A corrosion-resistant fixture is divided so that a chemical reaction does not occur or hardly occurs in the corrosive environment in the corrosive environment, and a member lacking affinity for metal is interposed between the divided pieces. A method for preventing corrosion of a connection portion, wherein a component having no corrosion resistance is screwed or inserted into a fixture in a state where the component is not attached.